942 resultados para Asphalt in hydraulic engineering.
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For the past several year Kossuth County has had a scheduled maintenance program of bituminous seal coating. This program has been used to maintain the 467 miles of asphaltic concrete surfaced roads in Kossuth County. Since most of the experience that Kossuth County had in seal coating was with cutback asphalt, it was decided to include the use of emulsified asphalt in Kossuth County's 1980 seal coat program. Federal Demonstration Project Funds were requested from the Federal Highway Administration to study the use of emulsified asphalt and funding was granted under Demonstration Project No. 55,:Asphalt Emulsions for Highway Construction." Items studied were design and construction procedure cost of alternate material, energy consumption and environmental considerations. A construction contract was awarded to Everds Brothers, Inc. of Algona, Iowa, on July 1, 1980. There were four bidders on the 54.5 miles of seal coating that was let. A map showing the location of the seal coating projects is shown in Appendix A, and a copy of the contract is shown in Appendix B. The contractor started the project on July 11, 1980 and completed the project on August 1, 1980. Construction inspection and follow-up inspections of the project were conducted by personnel of the Kossuth County Engineer's Office and testing of the materials, friction testing and road rater testing were conducted by the Material's Department of the Iowa Department of Transportation.
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Bio-binders can be utilized as asphalt modifiers, extenders, and replacements for conventional asphalt in bituminous binders. From the rheology results of Phase I of this project, it was found that the bio-binders tested had good performance, similar to conventional asphalt, except at low temperatures. Phase II of this project addresses this shortcoming and evaluates the Superpave performance of laboratory mixes produced with the enhanced bio-binders. The main objective of this research was to develop a bio-binder capable of replacing conventional asphalt in flexible pavements by incorporating ground tire rubber (GTR) into bio-oil derived from fast pyrolysis of agriculture and forestry residues. The chemical compatibility of the new bio-binder with GTR was assessed, and the low-temperature performance of the bio-binders was enhanced by the use of GTR. The newly developed binder, which consisted of 80 percent conventional binder and 20 percent rubber-modified bio-oil (85 percent bio-oil with 15 percent GTR), was used to produce mixes at two different air void contents, 4 and 7 percent. The laboratory performance test results showed that the performance of the newly developed bio-binder mixes is as good as or better than conventional asphalt mixes for fatigue cracking, rutting resistance, moisture sensitivity, and low-temperature cracking. These results need to be validated in field projects in order to demonstrate adequate performance for this innovative and sustainable technology for flexible pavements.
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This contribution tries to do a geographical approach about the hydraulic works in the River Ter, in the area of the Selva county. The reflections included here are based in the considerations of the research contained in the book of the historian Gerard Buxeda recently published. The interest will be focused in the scale of the projects proposed, in the differentiation of their characteristics according to the zone where will be proposed, in the relation of these works with the policy and the ideology dominant in the state, etc. In short, the aim is to frame the hydraulic works in a larger context and with the geographical specifies during the period 1850-1930
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Lappeenrannan teknillisen korkeakoulun sähkötekniikan osasto muutti 1.8.2005 sähkötekniikan tutkinnon kaksiportaiseksi ja vastaamaan näin Bologna-prosessia ja Suomen yliopistolainsäädäntöä. Tutkinnonuudistuksen myötä osasto haluaa varmistaa sähkötekniikan tutkintojen laadun ja vertailtavuuden sekä parantaa opiskelijoidensekä henkilökunnan liikkuvuutta. Tutkintojen laatu ja vertailtavuus osoitetaan sähkötekniikan osaston benchmark-projektilla, jossa kerätään tietoja maisteri- ja tohtorintutkintoa tarjoavista eurooppalaisista yliopistoista. Diplomityö käsittää BM-projektin kolmannen vaiheen suunnittelun ja toteutuksen sisältäen teoriaa benchmark-projekteille tyypillisistä toimintatavoista. Hyväksi havaitut menetelmiä, kuten kyselyt ja matriisit, on tässä työssä otettu soveltuvin osin sähkötekniikan osaston BM-projektin työkaluiksi. Diplomityössä analysoidaan työkalujen avulla BM-kumppaneilta kerättyjä tietoja sekä esitetään ratkaisuja, miten sähkötekniikan osastolla voidaan jatkaa parhaiden toimintatapojen löytämistä.
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Software engineering is criticized as not being engineering or 'well-developed' science at all. Software engineers seem not to know exactly how long their projects will last, what they will cost, and will the software work properly after release. Measurements have to be taken in software projects to improve this situation. It is of limited use to only collect metrics afterwards. The values of the relevant metrics have to be predicted, too. The predictions (i.e. estimates) form the basis for proper project management. One of the most painful problems in software projects is effort estimation. It has a clear and central effect on other project attributes like cost and schedule, and to product attributes like size and quality. Effort estimation can be used for several purposes. In this thesis only the effort estimation in software projects for project management purposes is discussed. There is a short introduction to the measurement issues, and some metrics relevantin estimation context are presented. Effort estimation methods are covered quite broadly. The main new contribution in this thesis is the new estimation model that has been created. It takes use of the basic concepts of Function Point Analysis, but avoids the problems and pitfalls found in the method. It is relativelyeasy to use and learn. Effort estimation accuracy has significantly improved after taking this model into use. A major innovation related to the new estimationmodel is the identified need for hierarchical software size measurement. The author of this thesis has developed a three level solution for the estimation model. All currently used size metrics are static in nature, but this new proposed metric is dynamic. It takes use of the increased understanding of the nature of the work as specification and design work proceeds. It thus 'grows up' along with software projects. The effort estimation model development is not possible without gathering and analyzing history data. However, there are many problems with data in software engineering. A major roadblock is the amount and quality of data available. This thesis shows some useful techniques that have been successful in gathering and analyzing the data needed. An estimation process is needed to ensure that methods are used in a proper way, estimates are stored, reported and analyzed properly, and they are used for project management activities. A higher mechanism called measurement framework is also introduced shortly. The purpose of the framework is to define and maintain a measurement or estimationprocess. Without a proper framework, the estimation capability of an organization declines. It requires effort even to maintain an achieved level of estimationaccuracy. Estimation results in several successive releases are analyzed. It isclearly seen that the new estimation model works and the estimation improvementactions have been successful. The calibration of the hierarchical model is a critical activity. An example is shown to shed more light on the calibration and the model itself. There are also remarks about the sensitivity of the model. Finally, an example of usage is shown.
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Optimization models in metabolic engineering and systems biology focus typically on optimizing a unique criterion, usually the synthesis rate of a metabolite of interest or the rate of growth. Connectivity and non-linear regulatory effects, however, make it necessary to consider multiple objectives in order to identify useful strategies that balance out different metabolic issues. This is a fundamental aspect, as optimization of maximum yield in a given condition may involve unrealistic values in other key processes. Due to the difficulties associated with detailed non-linear models, analysis using stoichiometric descriptions and linear optimization methods have become rather popular in systems biology. However, despite being useful, these approaches fail in capturing the intrinsic nonlinear nature of the underlying metabolic systems and the regulatory signals involved. Targeting more complex biological systems requires the application of global optimization methods to non-linear representations. In this work we address the multi-objective global optimization of metabolic networks that are described by a special class of models based on the power-law formalism: the generalized mass action (GMA) representation. Our goal is to develop global optimization methods capable of efficiently dealing with several biological criteria simultaneously. In order to overcome the numerical difficulties of dealing with multiple criteria in the optimization, we propose a heuristic approach based on the epsilon constraint method that reduces the computational burden of generating a set of Pareto optimal alternatives, each achieving a unique combination of objectives values. To facilitate the post-optimal analysis of these solutions and narrow down their number prior to being tested in the laboratory, we explore the use of Pareto filters that identify the preferred subset of enzymatic profiles. We demonstrate the usefulness of our approach by means of a case study that optimizes the ethanol production in the fermentation of Saccharomyces cerevisiae.
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The relation between the equivalent roughness and different grain size percentiles of the sediment in gravel-bed rivers was determined under the hypothesis that the vertical distribution of the flow velocity follows a logarithmic law. A set of 954 data points was selected from rivers with gravel size sediment or larger, with a non-sinuous alignment and free of vegetation or obstacles. According to the results, the ks roughness is equivalent to approximately 2.4D90, 2.8D84, and 6.1D50. No correlation was detected between the sediment sorting and the sediment mobility index on one hand, and, on the other, the coefficient of proportionality of each grain size percentile.
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Today's business environment has become increasingly unexpected and fast changing because of the global competition. This new environment requires the companies to organize their control differently, e.g. by logistic process thinking. Logistic process thinking in software engineering applies the principles of production process to immaterial products. Processes must be optimized, so that every phase adds value to the customer, and the lead times can be cut shorter to meet the new customer requirements. The purpose of this thesis is to examine and optimize the testing processes of software engineering concentrating on module testing, functional testing and their interface. The concept of logistic process thinking is introduced through production process, value added model and process management. Also theory of testing based on literature is presented, concentrating on module testing and functional testing. The testing processes of the Case Company are presented together with the project models in which they are implemented. The real life practices in module testing and functional testing and their interface are examined through interviews. These practices are analyzed against the processes and the testing theory, through which ideas for optimizing the testing process are introduced. The project world of the Case Company is also introduced together with two example testing projects in different life cycle phases. The examples give a view of how much effort of the project is put in different types of testing.
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Työn tavoitteena oli määrittää myyntikonfiguraattorissa käytettävän tuotemallin yleinen rakenne. Ensin selvitettiin tuotemallin luomista ja konseptin suunnittelua kirjallisuuden ja asiantuntijoiden haastattelujen avulla. Asiantuntijoiden haastattelut toteutettiin vapaamuotoisesti kysymyslistaa apuna käyttäen. Tämän lisäksi työssä pohditaan sähköisen liiketoiminnan roolia sekä myyntikonfiguraattorin tulevaisuuden näkymiä. Diplomityössä käsitellään tuotemallia yleisellä tasolla. Toinen näkökulma käsittelee tuotemallia tietoteknisissä sovelluksissa käytettyjen menetelmien pohjalta. Tuotemallin muodostaminen aloitettiin asiakkaalle näkyvästä osasta eli myyntikonfiguraattorin ulkoasusta. Seuraava ongelma oli standardoida tuotetta ja tarjousta kuvaavat dokumentit globaalisti. Tähän ratkaisuun päädyttiin haastattelujen sekä asiantuntijoiden kokoontumisien pohjalta. Loppuosa diplomityöstä käsittelee myyntikonfiguraattorin asemaa kohdeyrityksen sähköisessä liiketoiminnassa sekä esittelee erään näkemyksen myyntikonfiguraattorin yhteenliittymästä asiakashallinta- ja tuotetiedonhallinta järjestelmiin. Diplomityössä saavutettiin asetetut tavoiteet: Myyntikonfigurattori yhtenäistää kohdeyrityksen hinnoittelua globaalisti, nopeuttaa tarjouksentekoprosessia, helpottaa uuden tuotteen lanseerausta ja standardoi tuotemallin globaalisti. Myyntikonfiguraattorin integrointi muihin tietojärjestelmiin tehostaa myynnin toimintoja. Haasteeksi jää loppukäyttäjien kannustaminen tehokkaaseen käyttöön sekä ylläpidon toteuttaminen. Ilman käyttäjiä ja heidän innostustaan voi projekti menettää johdon luottamuksen.
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This work presents an analysis of the assessment tools used by professors at the Universitat Politécnica de Catalunya to assess the generic competencies introduced in the Bachelor’s Degrees in Engineering. In order to conduct this study, a survey was designed and administered anonymously to a sample of the professors most receptive to educational innovation at their own university. All total, 80 professors responded to this survey, of whom 26% turned out to be members of the university’s own evaluation innovation group (https://www.upc.edu/rima/grups/grapa), GRAPA. This percentage represents 47% of the total GRAPA membership, meaning that nearly half of the professors most concerned about evaluation at the university chose to participate. The analysis of the variables carried out using the statistical program SPSS v19 shows that for practically 49% of those surveyed, rubrics are the tools most commonly used to assess generic competencies integrated in more specific ones. Of those surveyed, 60% use them either frequently or always. The most frequently evaluated generic competencies were teamwork (28%), problem solving (26%), effective oral and written communication (24%) and autonomous learning (13%), all of which constitute commonly recognized competencies in the engineering profession. A two-dimensional crosstabs analysis with SPSS v19 shows a significant correlation (Asymp. Sig. 0.001) between the type of tool used and the competencies assessed. However, no significant correlation was found between the type of assessment tool used and the type of subject, type of evaluation (formative or summative), frequency of feedback given to the students or the degree of student satisfaction, and thus none of these variables can be considered to have an influence on the kind of assessment tool used. In addition, the results also indicate that there are no significant differences between the instructors belonging to GRAPA and the rest of those surveyed
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Biodegradable polyurethanes (PUR) were prepared from polyols derived from castor oil by transesterification of pentaerythritol-modified castor oil and lysine polyisocyanates (LDI and LTI). The polyurethanes obtained were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA), and dynamic mechanical thermal analysis (DMTA). The mechanical behavior of the polyurethanes was measured by Shore A hardness and tensile testing (stress-strain curves). The biodegradable nature of the material was determined by contact angle, water absorption tests, and in vitro degradation in PBS solution. This study aims to examine the effect of the structure and functionality of diisocyanate on the mechanical properties and in vitro degradation of the material. The results were compared with homologous materials obtained from isophorone diisocyanate (IPDI) used in previous works. The objective was to evaluate candidate materials that can be potentially used in tissue engineering.
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Transitional flow past a three-dimensional circular cylinder is a widely studied phenomenon since this problem is of interest with respect to many technical applications. In the present work, the numerical simulation of flow past a circular cylinder, performed by using a commercial CFD code (ANSYS Fluent 12.1) with large eddy simulation (LES) and RANS (κ - ε and Shear-Stress Transport (SST) κ - ω! model) approaches. The turbulent flow for ReD = 1000 & 3900 is simulated to investigate the force coefficient, Strouhal number, flow separation angle, pressure distribution on cylinder and the complex three dimensional vortex shedding of the cylinder wake region. The numerical results extracted from these simulations have good agreement with the experimental data (Zdravkovich, 1997). Moreover, grid refinement and time-step influence have been examined. Numerical calculations of turbulent cross-flow in a staggered tube bundle continues to attract interest due to its importance in the engineering application as well as the fact that this complex flow represents a challenging problem for CFD. In the present work a time dependent simulation using κ – ε, κ - ω! and SST models are performed in two dimensional for a subcritical flow through a staggered tube bundle. The predicted turbulence statistics (mean and r.m.s velocities) have good agreement with the experimental data (S. Balabani, 1996). Turbulent quantities such as turbulent kinetic energy and dissipation rate are predicted using RANS models and compared with each other. The sensitivity of grid and time-step size have been analyzed. Model constants sensitivity study have been carried out by adopting κ – ε model. It has been observed that model constants are very sensitive to turbulence statistics and turbulent quantities.
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Project management has evolved in recent decades. Project portfolio management, together with multi project management, is an emerging area in the project management field in practice, and correspondingly in academic research and forums. In multi project management, projects cannot be handled isolated from each other, as they often have interdependencies that have to be taken into account. If the interdependencies between projects are evaluated during the selection process, the success rate of the project portfolio is increased. Interdependencies can be human resources, technological, and/or market based. Despite of the fact that interdependency as a phenomenon has roots in the 1960s and is related to famous management theories, it has not been much studied, although in practice most companies use it to great extent. There exists some research on interdependency, but prior publications have not emphasized the phenomenon per se, because a practical orientation practitioner techniques prevails in the literature. This research applies the method triangulation, electronic surveys and multiple case study. The research concentrates on small to large companies in Estonia and Finland, mainly in construction, engineering, ICT, and machinery industries. The literature review reveals that interdependencies are deeply involved in R&D and innovation. Survey analysis shows that companies are aware of interdependency issues in general, but they i have lack of detailed knowledge to use it thoroughly. Empirical evidence also indicates that interdependency techniques influence the success rate and other efficiency aspects to different extents. There are a lot of similarities in interdependency related managerial issues in companies of varying sizes and countries in Northern Europe. Differences found in the study are for instance the fact that smaller companies face more difficulties in implementing and evaluating interdependency procedures. Country differences between Estonia and Finland stem from working solutions to manage interdependencies on a daily basis.historical and cultural reasons, such as the special features of a transition country compared to a mature country. An overview of the dominant problems, best practices, and commonly used techniques associated with interdependency is provided in the study. Empirical findings show that many interdependency techniques are not used in practice. A multiple case study was performed in the study to find out how interdependencies are managed in real life on a daily basis. The results show that interdependencies are mostly managed in an informal manner. A description of managing the interdependencies and implementation procedures is given. Interdependency procedures are hard to implement, especially in smaller companies. Companies have difficulties in implementing interdependency procedures and evaluating them. The study contains detailed results on how companies have implemented working solutions to manage interdependencies on a daily basis
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Kemiantekniikan kandidaatin ja diplomi-insinöörin tutkinto-ohjelmien itsearviointiraportissa käsitellään tutkinto-ohjelmien osaamistavoitteita ja niiden saavuttamista. Raportissa käydään läpi myös käytössä olevat resurssit sekä tutkinto-ohjelmiin liittyviä tunnuslukuja. Itsearviointi on toteutettu kansainvälisen akkreditointijärjestön kriteerien mukaisesti (ASIIN ja EUR-ACE).
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In many engineering applications, compliant piping systems conveying liquids are subjected to inelastic deformations due to severe pressure surges such as plastic tubes in modern water supply transmission lines and metallic pipings in nuclear power plants. In these cases the design of such systems may require an adequate modeling of the interactions between the fluid dynamics and the inelastic structural pipe motions. The reliability of the prediction of fluid-pipe behavior depends mainly on the adequacy of the constitutive equations employed in the analysis. In this paper it is proposed a systematic and general approach to consistently incorporate different kinds of inelastic behaviors of the pipe material in a fluid-structure interaction analysis. The main feature of the constitutive equations considered in this work is that a very simple numerical technique can be used for solving the coupled equations describing the dynamics of the fluid and pipe wall. Numerical examples concerning the analysis of polyethylene and stainless steel pipe networks are presented to illustrate the versatility of the proposed approach.